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Journal of Earth Science 2024年

作者： Tatiana Osipova Gennadiy Kallistov Maria Chervyakovskaya Vasiliy Chervyakovskiy Zavaritsky Institute of geology and Geochemistry Ural Branch of ras

Field- and petrographic investigations， together with microanalytical major- and trace-element studies， were carried out on clinopyroxene and amphibole from high-Mg diorite in the subduction-related Chelyabinsk granitic massif to understand its petrogenesis and source. The clinopyroxene composition (high Mg#， Cr-content， sum of REE and Ti/Eu ratio; depletion in HREE; negative Eu-anomaly) indicates that it formed from a reduced melt derived from a mantle source metasomatized by fluids/melts having crustal affinity. Melt compositions in equilibrium with clinopyroxene and amphibole were calculated using solid/liquid partition coefficients. The high Nb/Y and Zr/Y ratio values of a liquid simulated from clinopyroxene， which appears to have very similar characteristics to sanukitoid melts， indicate a low degree of melting of the mantle source. Melt simulated from amphibole is more evolved and more felsic (dacitic). It displays a geochemical “amphibole fractionation” signature， indicating the peritectic transformation of clinopyroxene to amphibole in the lower crust. Rock textures and major element mineral compositions suggest that further amphibole was precipitated directly from the melt in the middle crust. The results show that the Chelyabinsk high-Mg diorite was probably formed as a cumulate from sanukitoid-like melt during its ascent and cooling below dacitic liquidus inside the amphibole stability field.

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Zircon U-Pb ages in the Nuratau ophiolitic mélange in the southern Tianshan,Uzbekistan:Implication for the closure of Paleo-Asian Ocean

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China geology 2024年第2期7卷 365-368,I0004-I0007页

作者： Kai Weng Ji-fei Cao Divayev-Farid Karibovich Jahongir-Jurabekovich Movlanov Bo Chen Zhong-ping Ma Xi’an Center of Geological Survey China Geological SurveyXi’an 710119China The Center for Geoinnovation Technologies Doctor of Sciences in geology and mineralogy University of Geological ScienceTashkent 100060Uzbekistan

*** The Central Asian Orogenic Belt(CAOB),which is located between the European craton,Siberian craton,and Tarim-North China craton(Fig.1a),is the largest phanerozoic accretionary orogen in the *** resulted from the longterm subduction and accretion of the Paleo-Asian Ocean(PAO).The PAO has been in existence since at least the late Mesoproterozoic(about 1020 Ma).However,there has been debate about the closing time of the PAO.

关键词： Asian Paleo Tianshan

Newly identified Au-Ag-Bi-Te mineralization in the Aydindere skarn Fe and Cu deposit， Giresun， NE Turkey: implications of gold mineralization during retrograde skarn evolution

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Journal of Earth Science 2024年

作者： Ahmet Sasmaz Vitaliy Sukach Serhiy Bondarenko Hryhorii Aleksiienko Hengameh Erfanian Kaseb Bilge Sasmaz Sergiy Kurylo Oleksandr Hrinchenko Volodymyr Somka Panagiotis Voudouris Department of geology Firat University Faculty of geology and Geoenvironment National and Kapodistrian University of Athens mineralogy and Ore Formation of National Academy of Science M.P.Semenenko Institute of Geochemistry 3. Department of Petroleum Engineering Eqbal Lahoori Institute of Higher Education

This study investigates the mineralogy and mineral-chemistry of a newly discovered Au-Ag-Bi-Te mineralization at the Aydindere Fe-Cu skarn deposit， within the Pontides Tectonic Unit， northeastern Turkey. The mineralization is developed in the skarn zone at the contact between Upper Cretaceous andesite-pyroclastic rocks and a Paleocene-Eocene I-type granitoid. The principal ore minerals of the Aydindere Fe-Cu deposit are oxides (magnetite)， sulfides (pyrite-chalcopyrite-galena-sphalerite)， tellurides/sulfotellurides (tetradymite， hessite)， sulfosalts (wittichenite， emplectite， aikinite) and native gold-electrum. Skarn minerals include anhydrous phases (garnet) formed in a prograde stage and hydrous phases (amphibole， epidote， chlorite)， which were formed in a retrograde stage in association with quartz， adularia， apatite and late calcite. Sulfides， tellurides and sulfosalts are introduced during the retrograde stage. The Au-Ag-Bi-Te mineralization was detected for the first time within the western ore body of the Aydindere deposit， and occurs in calcite-bearing sulfide bodies that cut magnetite-garnet-amphibole-epidote skarns with magnetite ores of different grade， including massive magnetite. Chlorite geothermometry indicates formation of the Au-Ag-Bi-Te mineralization at temperatures between 300 and 250 °C， during the retrograde skarn evolution. Assuming the temperature is ～275°C， logfS2= -10.5 to -13， logfO2= -37 to -33， and logfTe2values range from approximately -12 to -8.5 were estimated. The available mineralogical and geological data (presences of magnetite， oxidized-type tellurides/sulfotellurides， and andraditic garnets， and absence of pyrrhotite and arsenopyrite) suggest that Aydindere is an oxidized Au-bearing skarn deposit. The discovery of Au-Ag-Bi-Te mineralization at Aydindere increases its productivity and requires more detailed exploration in the deposit for precious (Au， Ag) and critical (Bi， Te) metals.

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mineralogy and geochemistry of trachytic rocks from the Lichi Volcanics, Eastern Himalaya: insights into the Kerguelen mantle plume activity in the Eastern Himalayan Region

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Acta Geochimica 2024年第1期43卷 180-197页

作者： Pallabi Basumatary Deepshikha Borah Hiredya Chauhan Tribujjal Prakash Bibhuti Gogoi Department of geology Cotton UniversityGuwahatiAssam 781001India Wadia Institute of Himalayan geology DehradunUttarakhand 248001India

The Lichi volcanics are a suite of mafic-intermediate-felsic rocks and are considered coeval with the Abor volcanics(~132 Ma) of the Siang window in the Eastern Himalaya. Here, we present the first report of trachytic rocks from the Lichi volcanics, which are exposed in the Ranga valley, along the Kimin-Yazali road section in the Eastern Himalayan Region, Northeast India. The trachytes occur in close association with sandstones of the Gondwana Group of rocks and are characterised based on field, petrographical, and geochemical *** fine-grained trachytes are composed of alkali feldspar, biotite, plagioclase, sodic-amphibole, apatite, illmenite, and titanite. The REE profiles of the evolved trachytic rocks(higher SiO_(2)content) display fractionated trends. The fractionation of accessory mineral phases, like apatite and titanite, was possibly responsible for the strongly fractionated REE patterns of the evolved *** trachytic rocks demonstrate high apatite saturation temperatures of 988 ± 14 ℃(1σ, n = 8). The Aluminium Saturation Index(< 1.1) and binary discrimination diagrams of these peralkaline trachytes define their affinity with A-type granitoids. Elemental ratios like Y/Nb, Nb/U,and Ce/Pb signify that the Lichi trachytes are differentiated products of mantle-derived ocean island basalts. Trace elemental discrimination diagrams Th/Yb versus Nb/Yb, Y versus Nb, and Y + Nb versus Rb reflect a within-plate tectonic regime for the trachytes. From the results presented in this work, we infer that the development of rifting events during the breakup of eastern Gondwana due to the onset of Kerguelen plume activity further led to underplating of basic magma in lower crustal levels. These parental basaltic magmas underwent fractionation processes forming differentiated trachyandesites and *** into consideration the similarities recorded between the Lichi volcanics and Abor volcanics, this study supports the idea that Kerguelen plume ac

关键词： Peralkaline trachytes Trachyandesites A-type granitoids Apatite saturation temperature Abor volcanics Eastern Gondwana

Scavenging and release of REE and HFSE by Na-metasomatism in magmatic-hydrothermal systems

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Fundamental Research 2024年第2期4卷 315-323页

作者： Wu-Bin Yang He-Cai Niu Ning-Bo Li Pete Hollings Shannon Zurevinski Roger H.Mitchell Key Laboratory of mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China Department of geology Lakehead UniversityThunder BayON P7B 5E1Canada

Exploitable or potentially exploitable deposits of critical metals,such as rare-earth(REE)and high-field-strength elements(HFSE),are commonly associated with alkaline or peralkaline igneous ***,the origin,transport and concentration of these metals in peralkaline systems remains poorly *** study presents the results of a mineralogical and geochemical investigation of the Na-metasomatism of alkali amphiboles and clinopyroxenes from a barren peralkaline granite pluton in NE China,to assess the remobilization and redistribution of REE and HFSE during magmatic-hydrothermal *** amphiboles and aegirine-augites from the peralkaline granites show evolutionary trends from sodic-calcic to sodic compositions,with increasing REE and HFSE concentrations as a function of increasing Na-index[Na^(#),defined as molar Na/(Na+Ca)ratios].The Na-amphiboles(i.e.,arfvedsonite)and aegirine-augites can be subsequently altered,or breakdown,to form hydrothermal aegirine during late-or post-magmatic *** compositions analyzed by insitu LA-ICPMS show that the primary aegirine-augites have high and variable REE(2194-3627 ppm)and HFSE(4194-16,862 ppm)contents,suggesting that these critical metals can be scavenged by alkali amphiboles and *** to the primary aegirine-augites,the presentative early replacement aegirine(Aeg-I,Na^(#)=0.91-0.94)has notably lower REE(1484-1972)and HFSE(4351-5621)*** contrast,the late hydrothermal aegirine(Aeg-II,Na^(#)=0.92-0.96)has significantly lower REE(317-456 ppm)and HFSE(6.44-72.2 ppm)*** that the increasing Na^(#)from aegirine-augites to hydrothermal aegirines likely resulted from Na-metasomatism,a scavenging-release model can explain the remobilization of REE and HFSE in peralkaline granitic *** scavenging and release of REE and HFSE by Na-metasomatism provides key insights into the genesis of globally significant REE and HFSE *** high Na-index of th

关键词： Critical metals Alkali amphiboles Na-metasomatism REE and HFSE Na-index(Na^(#))

Age and geochemical evolution of granite magmatism in Olkhon region from Caledonian syncollisional ore-free granite to the rare metal granite and pegmatite of Middle Paleozoic intraplate setting

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China geology 2024年第1期7卷 63-79页

作者： Viktor Antipin Valentina Makrygina Larisa Kushch Nataliya Sheptyakova Vinogradov Institute of Geochemistry SB RAS664033 IrkutskRussia

The detailed description of two granite complexes in the Olkhon subterrane is *** Early Paleozoic Sharanur complex was formed by granitization of gneisses of the Olkhon *** includes migmatites,granite-gneisses,granites and pegmatites of normal alkalinity;they belong to the type of syncollisional *** Middle Paleozoic Aya granite complex includes mother Aya massif of amazonite-bearing granites and several types of rare-metal *** have elevated alkalinity,low of Ba,Sr,and high LILE and HFSE elements *** Aya pegmatites lie in northwest cracks of stretching and associated with the rise of the territory under the influence of the North Asian *** cracks and pegmatites mark the beginning of a new intraplate geodynamic *** geochemical types are distinguished among the pegmatites of this *** are amazonite pegmatites of Li-F type with Ta mineralization and complex type pegmatite with Be-Rb-Nb-Ta and Li-F mineralization(the Ilixin vein).The Tashkiney pegmatite vein is similar to Ilixin,but lies in the gneisses of the Olkhon *** shows high concentrations of Be,Nb,Ta,as well as W,Sn,but lacks Li and F,due to a greater depth and higher temperature of the melt crystallization of this pegmatite.

关键词： Pegmatite Geochemistry Submantle plume Magmatism Caledonian collision Middle Paleozoic intraplate setting Be-Rb-Nb-Ta-Li-F mineralization Olkhon region Russia

The Origin of Mesozoic A-type Granitoids,Fujian Province,Southeast China:Insights from Geochronology,mineralogy and Geochemistry

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 630-640页

作者： XIE Qifeng DONG Yunpeng CAI Yuanfeng ZHAI Mingguo XIAO Aifang ZHANG Hong Zijin School of geology and Mining Fuzhou UniversityFuzhou 350108China State Key Laboratory of Continental Dynamics Northwest UniversityXi’an 710069China State Key Laboratory for Mineral Deposits Research Nanjing UniversityNanjing 210023China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The magma sources,origins and precise forming ages of the miarolite from Qishan and Kuiqi intrusions are still *** results reveal that,miarolites from the Qishan and Kuiqi intrusions yield crystallization ages of~101 and~98 Ma,and they have a high formation temperature(~910℃)and low oxygen fugacity value,indicating crystallization condition at low pressure in the upper crust with temperature of 678℃.The Qishan and Kuiqi miarolites are characterized by enrichment in SiO_(2) and high-K alkali,depletion in Ca and Mg,and belong to the high-K weak peraluminous rock *** samples are enriched in HFSEs(i.e.,Ta,Zr and Hf)and LILEs(i.e.,Ba,P and Sr),depleted in Ba and Sr with the negative anomaly of *** the primitive mantle normalized trace element spider diagram,the samples show a right-inclined‘seagull-type’pattern,combined the ratios of(La/Yb)_(N),10000×Al/Ga,Rb/Nb and Nb/Ta etc.,they were proved to be alkaline A-type *** the characterize of the trace elements,they were derived from clay-rich source accompanied pelite melting,and subjected to K-feldspar crystallization *** values of ε_(Hf)(t)and tDM2 are distributed in the range of-2.8 to 3.3 with~1.2 Ga,and-6.0 to 4.0 with~1.2 Ga,revealing that they were generated from the Mesoproterozoic Cathaysia basement *** comprehensive research reveals the Kuiqi and Qishan intrusions derived from crust-mantle mixing and partial melting of the crust,respectively,resulting from lithospheric extension generated by the Paleo-Pacific Plate subducted into the European-Asian Plate.

关键词： A-type granitoid geochronology extension subduction Mesozoic Southeast China

Effect of alumina occurrence form on metallurgical properties of hematite and magnetite pellets

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Journal of Iron and Steel Research(International) 2024年第4期31卷 797-809页

作者： Jian Pan Chen-mei Tang Cong-cong Yang De-qing Zhu Zheng-qi Guo Wei-qun Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Exploration and Development of geology and Mineral Resources Co. Ltd.Nanchang 330030JiangxiChina

The effect of alumina occurrence form on the metallurgical properties of both hematite and magnetite pellets was investigated at the same Al_(2)O level of 2 wt.%,including reduction index(RI),low-temperature reduction disintegration index(RDI),reduction swelling index(RSI),and high-temperature softening-dripping *** mineralogy of fired pellets was also studied to reveal the influence of alumina occurrence form on the phase composition and *** the results,the alumina occurrence form presents tremendous impacts on the metallurgical perfor-mance of both magnetite and hematite *** of all alumina occurrence forms contributes to inferior reducibility of pellets,especially in the case of gibbsite for magnetite pellets with a RI of 58.4%and kaolinite for hematite pellets with a RI of 56.8%.However,addition of all alumina occurrence forms improves the RDI of magnetite pellets,while there is no significant difference among various alumina occurrence *** contrast,alumina occurrence forms have little influence on the RDI of hematite *** presence of free alumina,gibbsite,and kaolinite tends to improve the RSI of hematite and magnetite pellets,whereas hercynite gives the opposite trend with a RSI of 25.6%.For softening-dripping performance of magnetite pellets,all alumina occurrence forms contribute to narrower softening-melting ***,alumina,gibbsite,and kaolinite give narrower softening-dripping interval,at 229,217,and 88℃,respectively,whereas addition of hercynite results in the largest melting range at 276℃ due to its high melting *** hematite pellets,free alumina,gibbsite,and hercynite tend to enlarge melting range,whereas kaolinite contributes to lower dripping temperature of 1148℃ and narrow softening-dripping interval of 88℃ due to the formation of a greater amount of slag phase at high temperatures.

关键词： Oxidized pellet Magnetite Hematite Alumina occurrence form Metallurgical performance Blast furnace

Rare-Element Pegmatites Rocks Rich and Li of the Aïr Massif of the Tchirozerine: mineralogy and Chemical Composition Agadez Region-Northem Niger

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Open Journal of Applied Sciences 2024年第1期14卷 171-181页

作者： Ntoumbé Mama Hamza Bassara Amaya Adama Awona Paul Zéphyrin Nomenjanahary Limbisoa Department of Mines geology School of Geology and Mining Engineering University of Ngaoundere Meiganga Cameroon Department of geology Faculty of Sciences and Technic University of Abdou Moumouni Niger Department of Geomatic and geology Mapping School of Geology and Mining Engineering University of Ngaoundere Meiganga Cameroon National Advance School of Engineering of Yaounde Yaounde Cameroon School of Thematic Doctoral Faculty of Sciences University of Antsiranana Antsiranana Madagascar

The lithium potential in the Aïr massif is represented by mineral index of spodumene pegmatites and, lepidolite pegmatites. The mineral deposits of lithium occur in cluster or veins that cut the host rock or are located near the contact between the greenstone belt and granitic massif. The evidence of lithium is in the form of clusters or disseminated and stockwerk. Mineralogical characteristics show similarities between the Air Massif pegmatites and indicate the same homogenous source during the magma-generation process. The pegmatite rocks attracted the attention due to their wide exposure and composition, well appearance, and economically hosting of significant rare earth metals such as Sn and W. The mineralogical and petrographical investigations on the eight pegmatites rocks samples observed have a relative similarity, while a little difference in the shapes attributed to the ratio in the pegmatite rocks of the minerals. The occurrence of the kink band indicates the influence of the tectonic processes which affected the Aïr massif after the emplacement of late magmatic or post-magmatic pegmatites by injection into fractured rocks in the upper part of the crust. The Air Massif pegmatite has higher concentrations Li and of all trace elements except Hf and occasionally Zr, Ti, Sn and Mg of for the economic exploration.

关键词： Pegmatite Lithium Rare Elements Hydrothermal Processes Aïr Massif

Comparison of mantle lithosphere beneath early Triassic kimberlite fields in Siberian craton reconstructed from deep-seated xenocrysts

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Geoscience Frontiers 2016年第4期7卷 639-662页

作者： I.V.Ashchepkov S.S.Kuligin N.V.Vladykin H.Downes M.A.Vavilov E.N.Nigmatulina S.A.Babushkina N.S.Tychkov O.S.Khmelnikova lnstitute of geology and mineralogy sd ras Koptyug ave 3NovosibirskRussia Institute of Geochemistry sd ras Favorskky str laIrkutskRussia Department of Earth and Planetary Sciences Birkbeck University of LondonLondonUK Institute of geology of Diamonds and Noble metals sd ras Lenina ave 39YakutskRussia

Mantle xenocrysts from early Triassic kimberlite pipes from Kharamai, Ary-Mastakh and Kuranakh fields in the Anabar shield of Siberia revealing similar compositional trends were studied to estimate the superplume influence on the subcratonic lithosphere mantle （SCLM）. Pressure-temperature （PT） reconstructions using monomineral thermobarometry for 5 phases show division of the SCLM beneath the Kharamai field into 6 units： pyroxenitic Fe-rich （1-2 GPa） and Mg-rich （2-3 GPa） layers; middle with two levels of Gar-Sp pyroxenites at - 3 and 4-5 GPa; Gar-dunite-harzburgites - 4.5-6.5 GPa subjected to llm-Px vein metasomatism; and a Mg-rich dunite lower part. In the Anabar shield （Ary-Mastakh, Dyuken and Kuranakh fields） mantle lithosphere is composed of three large units divided into two parts： upper part with amphiboles and phlogopite; two levels of pyroxenites and eclogites at 3 and 4 GPa, and a lower part composed of refertilized dunites. Diagrams showing P-Fe#Gar clusters for garnets and omphacites illustrate the differences between SCLM of these localities. Differences of Triassic SCLM from Devonian SCLM are in simple layering; abundance of Na-Cr-amphiboles and metasomatism in the upper SCLM part, thick pyroxenite-eclogite layer and lower part depletion, heated from SCLM base to 5.0 GPa. Kharamai mantle clinopyroxenes represent three geochemical types：（1） harzburgitic with inclined linear REE, HFSE troughs and elevated Th, U; （2） lherzolitic or pyroxenitic with round TRE patterns and decreasing incompatible elements; （3） eclogitic with Eu troughs, Pb peak and high LILE content. Calculated parental melts for garnets with humped REE patterns suggest dissolution of former Cpx and depression means Cpx and garnets extraction. Clinopyroxenes from Ary-Mastakh fields show less in- dined REE patterns with HMREE troughs and an increase of incompatible elements. Clinopyroxenes from Kuranakh field show flatter spoon-like REE patterns and peaks in Ba, U, Pb and St, similar to th

关键词： Mantle lithosphere Monomineral thermobarometry Mineral geochemistry Triassic kimberlite Layering